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"Stop error 0xA5"error message when you dock a Windows 2000-based portable computer to a docking station while the computer is running

This article has been archived. It is offered "as is" and will no longer be updated.

For a Microsoft Windows XP version of this article, consult the following Microsoft Knowledge Base article:
840171 PC cards attached to a multifunction PCI-PCI bridge may not be recognized by the operating system
When you dock a Microsoft Windows 2000-based portable computer to a docking station while the computer is running, the computer quits unexpectedly, and then you receive the following error message on a blue screen.
A problem has been detected and Windows has been shut down to prevent damage to your computer...
Technical information:

*** STOP: 0x000000A5 (0xParameter_1, 0xParameter_2, 0xParameter_3, 0xParameter_3)
The ACPI Bios in this system is not fully compliant to the specification. Please read the Readme.txt for possible workarounds, or contact your system vendor for an updated bios.

The bios in this system is not fully ACPI compliant. Please contact your system vendor for an updated bios. If you are unable to obtain an updated bios or the latest bios supplied by your vendor is not ACPI compliant, you can turn off ACPI mode during text mode setup. To do this, simply press the F7 key when you are prompted to install storage drivers. The system will not notify you that the F7 key was pressed--it will silently disable ACPI and allow you to continue your installation.
Note The four parameters in this error message may vary, depending on the cause of the Stop error.

When you insert a PC Card in the PC Card slot of a portable computer or of a docking station, Windows 2000 may not recognize the PC Card.
This problem occurs because the Advanced Configuration and Power Interface (Acpi.sys) in Windows 2000 does not correctly determine the hardware device type.

Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


No prerequisites are required.

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version            Size    File name   --------------------------------------------------------   15-Apr-2004  00:22  5.0.2195.6920     163,344  Acpi.sys
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
816915 New file naming schema for Microsoft Windows software update packages
824684 Description of the standard terminology that is used to describe Microsoft software updates
hot dock hot-dock Win2k win2000 PCI-PCI bridge

Article ID: 840172 - Last Review: 12/08/2015 06:54:18 - Revision: 4.6

Microsoft Windows 2000 Server, Microsoft Windows 2000 Professional Edition, Microsoft Windows 2000 Advanced Server

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